What are good CO2 levels and what can you do if they aren't good?
When people breathe out they expel CO2. Depending on the level of ventilation, this can be exhausted and the CO2 levels will stay low (good ventilation) or if it isn't good, the CO2 will build up and rise.
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When people breathe out they expel CO2. Depending on the level of ventilation, this can be exhausted and the CO2 levels will stay low (good ventilation) or if it isn't good, the CO2 will build up and rise.
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https://twitter.com/Jenn75879827/status/1493406878159622144
There is no hard cutoff with the different levels, but here is a guide.
<800 ppm is quoted a lot, but in my experience, classrooms can be much higher. Up to 1500 ppm can occur with ventilation not working perfectly (very common). > 2000 happens with bad ventilation.
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<800 ppm is quoted a lot, but in my experience, classrooms can be much higher. Up to 1500 ppm can occur with ventilation not working perfectly (very common). > 2000 happens with bad ventilation.
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CO2 levels measure how much air is shared or rebreathed. @DavidElfstrom prepared a table comparing CO2 levels to the % of rebreathed air. The more rebreathed air, the higher the risk of airborne transmission.
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https://twitter.com/DavidElfstrom/status/1485829682012504064?s=20&t=qNZeyKcrm3NRE7PjWAvgdw
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What can you do?
If you see high CO2 levels, you can notify the caretaker/facility manager that you suspect there is an issue with the ventilation. You can also see what the school board policies are about air quality and health and safety.
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If you see high CO2 levels, you can notify the caretaker/facility manager that you suspect there is an issue with the ventilation. You can also see what the school board policies are about air quality and health and safety.
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You can open the windows as much as tolerable - even if it's just a crack. Opening the door as well allows the room air to clear out faster.
You can check the ventilation to see if there is an airflow issue.
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You can check the ventilation to see if there is an airflow issue.
https://twitter.com/joeyfox85/status/1476217494658592769?s=20&t=qNZeyKcrm3NRE7PjWAvgdw
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Unfortunately, some schools are built in the 1950s era and are under-ventilated. You can't open the windows enough when it's -20 deg C outside. There's no simple fix for the ventilation and CO2 levels will be high.
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The only other solution is adding filtration - a HEPA filter or a #corsirosenthalbox . Filtration is an additional mitigation measure that can be used anywhere, but is especially important in these situations.
UVGI also works, but isn't used in most places.
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UVGI also works, but isn't used in most places.
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